Geometry definitions

Geometry definitions

Summary

ESDU 75031
gives an empirical method for the prediction of the drag increment due to a variety of two-dimensional excrescences,
each mounted normal to the flow direction on a flat plate, and immersed in a turbulent boundary layer for Mach numbers up to 3.
The excrescence types are

a forward-facing step, ramp (chamfered step), or a radiused step,

a rearward-facing step, ramp (chamfered step), or a radiused step,

a square section ridge or a rectangular section ridge (of height/length ratio 2), with or without radii to the top corners.

In this program the method of ESDU 73031 has tentatively been extended to cover situations in which steps
and ridges are inclined to the flow at other than 90 degrees, along the lines suggested
in ESDU 93032.